The invention relates to high voltage regulators, and more particularly high voltage regulators including a shunt regulator and/or a bandgap reference generator.
A conventional mixed mode integrated circuit system frequently uses different voltage supplies. Analog signal processing, such as amplification, comparison, and pulse generation, may be performed at high voltage. A FLASH memory applies an erase signal and a program signal to memory cells. The erase signal and the program signal have voltage levels greater than a supply voltage. Also in multilevel volatile memories, the variation of the voltage level of the program signal falls in a smaller range for the multibit signals stored in the memory cells.
A high voltage supply is typically used on-chip for non-volatile programming, erasing, and read operations. High voltage is generated typically from a charge pump utilizing capacitors. Regulation of the charge pumped high voltage provides precise voltage level for chip operation. The regulation is typically done using Zener-based techniques.